Fan hub configuration for an electric motor assembly

Abstract

A electric motor assembly includes an electric motor and a fan assembly coupled to the electric motor and configured to rotate therewith about an axis. The fan assembly includes a hub including a core ring, a first inner ring circumscribing the core ring, and a first plurality of circumferentially-spaced ribs extending between the core ring and the first inner ring. The hub also includes a second inner ring circumscribing the first inner ring and a second plurality of circumferentially-spaced ribs extending between the first inner ring and the second inner ring, and a plurality of circumferentially-spaced blades coupled to an outer periphery of the hub.

What is claimed is: 
     
       1. A fan hub for use in a fan assembly configured to rotate about an axis, said fan hub comprising:
 a core ring; 
 a first inner ring circumscribing said core ring; 
 a first plurality of circumferentially-spaced ribs extending between said core ring and said first inner ring, wherein the first plurality of ribs consists of ribs which are spaced about the entire circumferences of the core ring and the first inner ring; 
 a second inner ring circumscribing said first inner ring; and 
 a second plurality of circumferentially-spaced ribs extending between said first inner ring and said second inner ring, wherein the second plurality of ribs consists of ribs which are spaced about the entire circumferences of the first inner ring and the second inner ring, wherein the number of ribs of said first plurality of ribs is equal to the number of ribs of said second plurality of deformable ribs, wherein the second plurality of ribs is located radially outwardly of the first plurality of ribs, wherein said first plurality of ribs is circumferentially offset from said second plurality of deformable ribs; 
 wherein said second plurality of deformable ribs facilitate balancing said fan assembly. 
 
     
     
       2. The fan hub in accordance with  claim 1 , wherein each rib of said first plurality of ribs comprises a first radial length, and wherein each rib of said second plurality of ribs comprises a second radial length greater than the first radial length. 
     
     
       3. The fan hub in accordance with  claim 2 , wherein the second radial length is at least twice the first radial length. 
     
     
       4. The fan hub in accordance with  claim 1 , wherein at least one rib of said second plurality of deformable ribs comprises a rib void, said rib void comprising removed material to facilitate balancing said fan assembly. 
     
     
       5. The fan hub in accordance with  claim 1 , wherein each rib of said first plurality of ribs is connected to said first inner ring approximately midway between adjacent ribs of said second plurality of deformable ribs. 
     
     
       6. The fan hub in accordance with  claim 1 , further comprising an outer ring circumscribing said second inner ring to define a radial gap therebetween, wherein said radial gap forms a continuous circle about said second inner ring. 
     
     
       7. The fan hub in accordance with  claim 6 , wherein said radial gap is configured to receive at least one balancing weight. 
     
     
       8. A electric motor assembly comprising:
 an electric motor; and 
 a fan assembly coupled to said electric motor and configured to rotate about an axis, said fan assembly comprising:
 a hub comprising,
 a core ring; 
 a first inner ring circumscribing said core ring; 
 a first plurality of circumferentially-spaced ribs extending between said core and said first inner ring, wherein the first plurality of ribs consists of ribs which are spaced about the entire circumferences of the core ring and the first inner ring; 
 a second inner ring circumscribing said first inner ring; and 
 a second plurality of circumferentially-spaced deformable ribs to facilitate balancing said fan assembly, said second plurality of deformable ribs extending between said first inner ring and said second inner ring, wherein the second plurality of ribs consists of ribs which are spaced about the entire circumferences of the first inner ring and the second inner ring, wherein the number of ribs of said first plurality of ribs is equal to the number of ribs of said second plurality of deformable ribs, wherein the second plurality of ribs is located radially outwardly of the first plurality of ribs, wherein said first plurality of ribs is circumferentially offset from said second plurality of deformable ribs; and 
 
 a plurality of circumferentially-spaced blades coupled to an outer periphery of said hub. 
 
 
     
     
       9. The electric motor assembly of  claim 8 , wherein the quantity of ribs of said second plurality of deformable ribs is equal to a quantity of blades of said plurality of blades. 
     
     
       10. The electric motor assembly of  claim 8 , wherein each rib of said second plurality of deformable ribs is aligned with a circumferential midpoint of a corresponding blade of said plurality of blades along said outer periphery. 
     
     
       11. The electric motor assembly of  claim 8  further comprising at least one alignment device extending from said first inner ring. 
     
     
       12. The electric motor assembly of  claim 11 , wherein said electric motor comprises a rotor assembly comprising at least one alignment opening, wherein said at least one alignment device is configured to mate with at least one alignment opening. 
     
     
       13. The electric motor assembly in accordance with  claim 8 , further comprising an outer ring circumscribing said second inner ring, wherein said outer ring comprises a first axial height and said second inner ring comprises a second axial height less than the first axial height. 
     
     
       14. The electric motor assembly in accordance with  claim 13 , wherein said outer ring comprises a first radial thickness and said second inner ring comprises a second radial thickness. 
     
     
       15. A fan hub for use in a fan assembly configured to rotate about an axis, said fan hub comprising:
 a core ring; 
 a first inner ring circumscribing said core ring; 
 a first plurality of circumferentially-spaced ribs extending between said core ring and said first inner ring, wherein the first plurality of ribs consists of ribs which are spaced about the entire circumferences of the core ring and the first inner ring; 
 a second inner ring circumscribing said first inner ring; and 
 a second plurality of circumferentially-spaced deformable ribs extending between said first inner ring and said second inner ring, wherein the second plurality of ribs consists of ribs which are spaced about the entire circumferences of the first inner ring and the second inner ring, wherein the number of ribs of said first plurality of ribs is equal to the number of ribs of said second plurality of deformable ribs, wherein the second plurality of ribs is located radially outwardly of the first plurality of ribs, wherein said first plurality of ribs is circumferentially offset from said second plurality of deformable ribs; 
 wherein at least on rib of said second plurality of deformable ribs comprises a rib void, said rib void comprising removed material to facilitate balancing said fan assembly.